一筹 is a noun used almost exclusively in the fixed expression 高出一筹 or 略胜一筹, meaning 'a notch above' or 'slightly better than'. It refers to a small but noticeable advantage in skill, quality, or level — like being 'a cut above' in English. You'll rarely see it outside these comparative patterns; it's a literary or formal way to say someone or something edges out the competition.